Adhesions are fibrous bands of connective tissue that form between tissues and organs in the body that are not normally connected together, or that form in a way that is different from the normal connective tissue anatomy between tissues and organs in the body. Adhesions commonly form after surgery on the abdomen or the pelvic regions, though post-surgical adhesions may form anywhere in the body. In certain cases, adhesions may cause complications such as pain or obstruction of the organs to which they connect.
Adhesions generally begin forming shortly after surgery, and continue to develop thereafter. There are no known treatments to reverse adhesion formation. If adhesions lead to complications in the patient, the typical treatment is to remove them surgically. The best approach to adhesion management is prevention.
Various products are on the market for prevention of adhesion formation. These products are not 100% effective, though their use fairly consistently substantially reduces adhesion formation. These products take on many forms, such as gels and pastes that are applied to surgical sites within the body, and are gradually resorbed over a the course of a few days.
Another anti-adhesion product is a physical barrier, such as polytetrafluorethylene membranes. The barriers need not be permanent implants and, to this end, oxidized regenerated cellulose (ORC) sheets are commonly implanted within surgical sites. These ORC sheets are resorbed over the course of a few days, and are typically well-tolerated by patients.
Adhesions may be particularly troublesome when repairing soft tissue, such as a hernia, in which success and recovery of the procedure in both the short and long term may be determined in part by the biomechanical response of the graft used to repair the tissue. The compliance of the graft used to repair the tissue may largely affect outcome of the procedure; it is generally better to match the compliance of the tissue, and avoid both over-compliant and under-compliant implants. However the compliance of the implant may change over time, in part because of the tissue response, including the presence of adhesions. Adhesions may change the compliance of the implant.
Hernia repair surgery, which is a form of abdominal or pelvic surgery, often induces adhesion formation. Certain hernia repair procedures involve the implantation of synthetic or biologic mesh materials that support biologic loads at the site of herniation while the body repairs itself. But over time, these implanted hernia repair substrates may become progressively infiltrated with and covered with scar tissue, and themselves become a source of adhesions.
There remains a need for adhesion prevention and control, particularly with respect to hernia repair surgery. Further, there is generally a need for hernia repair grafts that are sufficiently compliant and that maintain their biomechanical properties, including compliance, over time while implanted into a patient.